The son of a musician, Tellier grew up in Paris, taking guitar and piano lessons and absorbing the albums his father played him, such as Pink Floyd's Atom Heart Mother. Aside from Serge Gainsbourg and Michel Polnareff, Tellier wasn't impressed with the French pop music he heard as a boy, preferring the music of François de Roubaix, Michel Legrand, and other home-grown soundtrack composers. When he began releasing music of his own, the French touch scene -- which included Phoenix and Air -- was beginning to gain traction. After Tellier's "Fantino," a forlorn and beautiful pop confection, appeared on the Source label's 1999 Source Material various-artists compilation, it caught the attention of Air's Nicolas Godin and Jean-Benoît Dunckel, and the duo eventually signed Tellier to their own Record Makers imprint. Tellier recorded the tracks for his debut album, L'Incroyable Vérité ("The Unbelievable Truth"), between September 1999 and March 2000, playing most of the instruments and producing the sessions. After L'Incroyable Vérité was released in June 2001, Tellier toured with Air extensively. He then began his second career as a film composer with the score to Gilles Lellouche and Tristan Aurouet's 2004 comedy Narco.
In January 2004, Tellier returned with his second album, Politics, which was produced by Cassius' Philippe Zdar and featured Mr. Oizo, the Bulgarian Symphony Orchestra, and Nigerian drummer Tony Allen of Fela Kuti fame. The album included the track "La Ritournelle," a song whose popularity was reflected in its numerous remixes by artists such as Metronomy. Politics reached 123 on France's Top Albums chart. The following year, Tellier re-recorded a batch of his songs acoustically with pianist Simon Dalmais and released them under the title Sessions in April 2006 (in the U.K., the collection was called Universe and included pieces from Tellier's Narco score). In 2007, Tellier reunited with Mr. Oizo on the soundtrack and score to Oizo's first feature film, Steak.
For his next record, February 2008's Sexuality, Tellier signed up Daft Punk's Guy-Manuel de Homem-Christo as producer and ended up with a more polished electronic sound than heard on his previous outings. The first single from the record, "Divine," was chosen as France's entry in the 2008 Eurovision contest. Though he didn't win, his appearance and the controversy surrounding it (many French commentators felt that the English lyrics of the song meant it wasn't "French" enough to represent the nation) boosted his profile around the world. Sexuality became a Top 40 album in France and also charted in Belgium and Sweden. A remix album, Sexuality Remix, followed in 2010.
Tellier returned in April 2012 with My God Is Blue. A spiritually minded set that featured co-production by Mr. Flash and Pavle Kovacevic as well as a collaboration with de Homem-Christo on the title track, it reached number 17 on France's Top Albums chart. The following October saw the release of Confection, a collection of tender instrumentals inspired in part by the death of his grandmother. Featuring pieces he had originally written for an unreleased soundtrack, the album peaked at 52 on the French charts. Also in 2013, Tellier collaborated with Chairlift's Caroline Polachek on the single "In the Crew of Tea Time." For his next album, L'Aventura, Tellier added sunny yet mysterious Brazilian elements to his music. Largely recorded at Jean Michel Jarre's studio in Bougival as well as in Paris, the album's basic tracks were expanded on in Rio de Janeiro by Brazilian luminaries such as percussionist Robertinho Silva and arranger Arthur Verocai. Upon its July 2014 release, L'Aventura peaked at 53 on France's Top Album chart.
In 2016, Tellier worked with Jarre on the latter's album Electronica, Vol. 2: The Heart of the Noise. That year, he composed the scores for the films Marie et les Naufragés and Saint Amour as well as the web series A Girl Is a Gun. He also collaborated with Dita Von Teese on a version of Culture Club's "Do You Really Want to Hurt Me" that appeared on an amfAR benefit compilation, setting the stage for his writing and production work on her 2018 self-titled debut album. Tellier returned in 2020, first appearing on Salvatore Ganacci's February single "Boycycle," and then in May with his own full-length Domesticated. Inspired by his day-to-day life at home as a husband and father, it included production work by Jam City and Zdar. That November, Tellier issued Simple Mind, a collection of reworkings of favorite songs from Domesticated, Sexuality, My God Is Blue, and L'Aventura. ~ Heather Phares & Bryan Thomas, Rovi